The PDS 70 planets have been found inside a large cavity (whose size depends on wavelength; [1]}, [2]}, [3]}, [4]}) that seems to be devoid of gas and dust,
except for some small amounts of various optically thin molecules [5]}.
To model the CSD of PDS 70,
[6]} and [7]} have an azimuthally averaged gas column density of \(\Sigma \sim 10^{-3}\)  cm\(^2\)  g\(^{-1}\)  at the location of PDS 70 b.
From Figure REF c, \(A_R\approx \kappa _{\mathrm {dust,\,H}\,\alpha }\Sigma \sim 10^{-4}\) –0.1 mag. This suggests that the CSD should not lead to any significant extinction.
Finally, PDS 70 c could be affected more severely by extinction because of its proximity to the gap edge [8]}. However, the extinction at ALMA wavelengths is not strong enough as to prevent the detection of a CPD around PDS 70 c [9]}.
